Please help me, i dunno what to do

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny

Write the expression 7x^3-28xy^2 as the product of 3 factors

What is the result of adding the system of equations? 2x+y=4 3x-y=6